First Crusade started in 1095 and was called by Pope Urban 2 as a way to unite waring European feudal states against a common enemy under the banner of Christian unity under the Pope. Mostly Frankish dukes were responsible for the effort. Anatolia and cites such as Antioch and Edessa were taken before Jerusalem in 1099.
The didn’t seem too serious from what’ you’re saying. 1492 was good for Spain. Is it too late to expel everybody again?
My point is that the Crusades consolidated power for the Catholic Church. The Byzantine empire was waning and The feudal states had to show fealty to Rome, is kiss the Popes ring.
The Pope responded to a call from the Byzantine Emperor Alexios in 1095 for help from the West against the Turks. It wasn’t like the Pope just said hey lets get all of Western Christendom to go to war. The war started when the Muslims invaded Iberia-Spain in the 7th century.